lmkd: Enable new kill strategy, add and adjust required system properties (a7af7348) · Commits · e / os / android_system_core

lmkd/README.md

+8 −0

Original line number	Diff line number	Diff line
		@@ -80,3 +80,11 @@ properties:
		the threshold when system does not recover even
		after a kill. Default for low-RAM devices = 50,
		for high-end devices = 10

		ro.lmk.psi_partial_stall_ms: partial PSI stall threshold in milliseconds for
		triggering low memory notification. Default for
		low-RAM devices = 200, for high-end devices = 70

		ro.lmk.psi_complete_stall_ms: complete PSI stall threshold in milliseconds for
		triggering critical memory notification. Default =
		700

lmkd/lmkd.c

+39 −6

Original line number	Diff line number	Diff line
		@@ -133,6 +133,11 @@
		/* ro.lmk.thrashing_limit_decay property defaults */
		#define DEF_THRASHING_DECAY_LOWRAM 50
		#define DEF_THRASHING_DECAY 10
		/* ro.lmk.psi_partial_stall_ms property defaults */
		#define DEF_PARTIAL_STALL_LOWRAM 200
		#define DEF_PARTIAL_STALL 70
		/* ro.lmk.psi_complete_stall_ms property defaults */
		#define DEF_COMPLETE_STALL 700

		/* default to old in-kernel interface if no memory pressure events */
		static bool use_inkernel_interface = true;
		@@ -174,6 +179,8 @@ static unsigned long kill_timeout_ms;
		static bool use_minfree_levels;
		static bool per_app_memcg;
		static int swap_free_low_percentage;
		static int psi_partial_stall_ms;
		static int psi_complete_stall_ms;
		static int thrashing_limit_pct;
		static int thrashing_limit_decay_pct;
		static bool use_psi_monitors = false;
		@@ -2406,8 +2413,15 @@ do_kill:
		}
		}

		static bool init_mp_psi(enum vmpressure_level level) {
		int fd = init_psi_monitor(psi_thresholds[level].stall_type,
		static bool init_mp_psi(enum vmpressure_level level, bool use_new_strategy) {
		int fd;

		/* Do not register a handler if threshold_ms is not set */
		if (!psi_thresholds[level].threshold_ms) {
		return true;
		}

		fd = init_psi_monitor(psi_thresholds[level].stall_type,
		psi_thresholds[level].threshold_ms * US_PER_MS,
		PSI_WINDOW_SIZE_MS * US_PER_MS);

		@@ -2415,7 +2429,7 @@ static bool init_mp_psi(enum vmpressure_level level) {
		return false;
		}

		vmpressure_hinfo[level].handler = mp_event_common;
		vmpressure_hinfo[level].handler = use_new_strategy ? mp_event_psi : mp_event_common;
		vmpressure_hinfo[level].data = level;
		if (register_psi_monitor(epollfd, fd, &vmpressure_hinfo[level]) < 0) {
		destroy_psi_monitor(fd);
		@@ -2439,14 +2453,29 @@ static void destroy_mp_psi(enum vmpressure_level level) {
		}

		static bool init_psi_monitors() {
		if (!init_mp_psi(VMPRESS_LEVEL_LOW)) {
		/*
		* When PSI is used on low-ram devices or on high-end devices without memfree levels
		* use new kill strategy based on zone watermarks, free swap and thrashing stats
		*/
		bool use_new_strategy =
		property_get_bool("ro.lmk.use_new_strategy", low_ram_device \|\| !use_minfree_levels);

		/* In default PSI mode override stall amounts using system properties */
		if (use_new_strategy) {
		/* Do not use low pressure level */
		psi_thresholds[VMPRESS_LEVEL_LOW].threshold_ms = 0;
		psi_thresholds[VMPRESS_LEVEL_MEDIUM].threshold_ms = psi_partial_stall_ms;
		psi_thresholds[VMPRESS_LEVEL_CRITICAL].threshold_ms = psi_complete_stall_ms;
		}

		if (!init_mp_psi(VMPRESS_LEVEL_LOW, use_new_strategy)) {
		return false;
		}
		if (!init_mp_psi(VMPRESS_LEVEL_MEDIUM)) {
		if (!init_mp_psi(VMPRESS_LEVEL_MEDIUM, use_new_strategy)) {
		destroy_mp_psi(VMPRESS_LEVEL_LOW);
		return false;
		}
		if (!init_mp_psi(VMPRESS_LEVEL_CRITICAL)) {
		if (!init_mp_psi(VMPRESS_LEVEL_CRITICAL, use_new_strategy)) {
		destroy_mp_psi(VMPRESS_LEVEL_MEDIUM);
		destroy_mp_psi(VMPRESS_LEVEL_LOW);
		return false;
		@@ -2831,6 +2860,10 @@ int main(int argc __unused, char **argv __unused) {
		property_get_bool("ro.config.per_app_memcg", low_ram_device);
		swap_free_low_percentage = clamp(0, 100, property_get_int32("ro.lmk.swap_free_low_percentage",
		low_ram_device ? DEF_LOW_SWAP_LOWRAM : DEF_LOW_SWAP));
		psi_partial_stall_ms = property_get_int32("ro.lmk.psi_partial_stall_ms",
		low_ram_device ? DEF_PARTIAL_STALL_LOWRAM : DEF_PARTIAL_STALL);
		psi_complete_stall_ms = property_get_int32("ro.lmk.psi_complete_stall_ms",
		DEF_COMPLETE_STALL);
		thrashing_limit_pct = max(0, property_get_int32("ro.lmk.thrashing_limit",
		low_ram_device ? DEF_THRASHING_LOWRAM : DEF_THRASHING));
		thrashing_limit_decay_pct = clamp(0, 100, property_get_int32("ro.lmk.thrashing_limit_decay",